The Living world

• Ecosystem


  All the living and non-living parts in an area
• Parts of an ecosystem

  • Biotic (living) parts (e.g. plants and animals)
  • Abiotic (non-living) parts (e.g. soil and climate)
• Organisms in ecosystems


  • Producers
  • Consumers
  • Decomposers
• Producer


  Organism that uses sunlight energy to produce food
• Consumer


  Organism that gets its energy by eating other organisms
• Decomposer


  Organism that gets its energy by breaking down dead material
• Nutrient cycle


  1. Plants absorb nutrients from the soil and use them to grow

  2. Plants drop their leaves

  3. Animals eat plants, taking in the nutrients they contain

  4. When dead material decomposes, nutrients are released into the soil

  5. The nutrients are then taken up from the soil by plants
• Nutrient cycling


  The transfer of nutrients through an ecosystem
• Food chain


  Shows what eats what
• Food web


  Shows lots of food chains and how they overlap
• Each part of an ecosystem depends on other parts
• If one part changes

  It affects all the other parts that depend on it
• The climate in an area determines what type of ecosystem forms
• Major global ecosystems


  • Tundra
  • Boreal forest
  • Grassland
  • Temperate deciduous forest
  • Tropical rainforest
  • Hot desert
  • Polar
• Tundra


  • Found at high latitudes, very cold winters, brief summers, little rainfall, hardly any trees, vegetation includes mosses and low shrubs, layer of permanently frozen ground
• Boreal forest


  • Found between 50-60°N, cold and dry winters, mild and moist summers, coniferous trees
• Grassland


  • Savannas have distinct dry and wet seasons, relatively low rainfall, mostly grasses with scattered trees; temperate grasslands have more variation in temperature and less rainfall, just grasses
• Temperate deciduous forest


  • Found in mid-latitudes, four distinct seasons, warm summers, relatively mild winters, rainfall all year round, deciduous trees that lose leaves in winter
• Tropical rainforest


  • Found around the equator, hot and wet all year round, lush forest with dense canopies forming distinct layers
• Hot desert


  • Found between 15-35° north and south of the equator, little rainfall, very hot during the day and very cold at night, shrubs and cacti sparsely distributed
• Polar


  • Found around the north and south poles, very cold and icy, dry, little growth, short growing season of about two months, long periods of darkness